H. Hunt Batjer, MD, FACS, FAANS (left)
Lois C. A. and Darwin E. Smith Distinguished Chair in Neurological Surgery
UT Southwestern Medical Center
Babu G. Welch, MD, FAANS (right)
Duke Samson Chair in Neurological Surgery
Professor of Neurosurgery and Radiology, UT Southwestern Medical Center
Chair, AANS/CNS Joint Cerebrovascular Section
As the saying goes, “It is difficult to make predictions, especially about the future.” While the past is not necessarily a clear guide for our future, over the past 90 years, dramatic progress has been made in the field of cerebrovascular neurosurgery. Walter E. Dandy, MD, reported the first case of clipping of an aneurysm in 1936, and this technique was a mainstay of treatment of aneurysms for decades until recently. Although the general idea remained the same for the subsequent 50 years, consider the following major advances over the last 30 years:
- Detachable coils reached clinical practice in the 1990s as a new treatment for cerebral aneurysms and other vascular disorders.
- Since then endovascular hybrid operating suites have proliferated, combining the advantages of open and endovascular techniques for cerebrovascular disorders.
- In the past several years, flow-diverting stents and other devices have come online, advancing endovascular techniques.
- In 2015, four endovascular stroke trials changed our treatment paradigm for patients with acute stroke. As a result, the indications for mechanical thrombectomy have expanded dramatically, and again the patient has benefitted from the ingenuity of cerebrovascular specialists.
One would anticipate that this pace of change will continue for the field. However, questions remain as to how new developments might create gains in the most vexing problems we currently face. Our management of giant thrombotic aneurysms, complex arteriovenous malformations, vertebrobasilar enlargement, and deep cavernous malformations continues to produce mixed results at best, and much remains to be improved in the management of these challenging disorders.
Viewing the future of cerebrovascular neurosurgery from an armchair of our species’ (and specialty’s) vision exceeds our current reach. Accordingly, we can envision a future that includes personalized treatments informed by advances in the understanding of the genetic underpinnings of cerebrovascular diseases. Advancements in engineering will complement this understanding. Further evolution of endovascular and stereotactic techniques will allow delivery of therapies via less invasive methods that minimize intrusion and speed recovery.
This potential future has major implications on how we maintain and improve the education standards of neurosurgical residency. The neurosurgical workforce in the United States must continue to influence neurosurgery on a global scale. Our contract with society requires that we modify our historical educational principles to provide a healthy and well-trained workforce not only for the population of the U.S. but also the world. To meet this responsibility, will we have to increase the duration of training? Will simulation-based models, including virtual and augmented reality, be adequate to replace hands-on training with new technologies without jeopardizing patient safety? Will 3D printing lead to economically viable treatment planning and new therapies?
The ratio of trainees to surgical cases, especially complex open cerebrovascular surgeries, is a delicate balance that is central to the training of a cerebrovascular neurosurgeon. As a result, there is the constant question of whether future trainees will be capable of handling complex open surgical challenges in the face of decreasing volumes? But are we training too many cerebrovascular specialists or are we incorrectly focusing on U.S. volumes while the world population continues to grow? While the annual incidence of stroke in the U.S. is estimated at 900,000, only 10 percent of that number is hemorrhagic disease. On a global scale, in younger adults aged 20 to 64 years, the prevalence of hemorrhagic stroke is 3.7 million cases. As the influence of capitalism continues to expand, it will only be financially viable for biotechnology companies to develop personalized interventions for hemorrhagic conditions when global volumes are considered. Many of the factors that will impact the global spread of cerebrovascular techniques are not very well understood and certainly beyond our control, including the health of the U.S. and global economies, geopolitical developments, and national and global regulatory environments concerning the development of new technologies.
Finally, artificial intelligence (AI) and machine learning will also play a role in the future of cerebrovascular neurosurgery. “Big data” will enable us to target more effectively and precisely new interventions than all of the past and highly-expensive prospective randomized clinical trials have ever done. Neurosurgeons of the future will also need fluency in the knowledge domains of genetics, stem-cell biology, neuromodulation, hematology (coagulation), molecular biology, precision medicine, artificial intelligence, simulation (including virtual and augmented reality), robotics, and endoscopy.
The bottom line for the future of cerebrovascular neurosurgery:
- Knowledge demands are increasing dramatically;
- Technical demands will also change dramatically;
- Open surgical experience will be reduced while the complexity of the cases will increase.
- AI, augmented reality, advanced simulation, and machine learning will improve training and conclusions from clinical practice yielding better decision-making;
- A global approach to cerebrovascular disease will be important for patients and trainees alike; and
- The best days for cerebrovascular neurosurgery and our patients are ahead.
Editor’s Note: We encourage everyone to join the conversation online by using the hashtag #VascularNeurosurgery.